摘要
<正>地震波沿自由表面传播入射角超过临界角时会产生面波现象。因此,地震波数值模拟中需要精确地处理自由表面边界以获取面波传播的数值解。由于边界两侧的物质属性差异,一般认为是物质/真空界面。物质间断面使面波模拟面临数值稳定问题。弹性介质中面波有限差分自由表面边界处理方法有近似真空法,假设网格上物质属性不连续满足自由表面边界条件(如Moczo et al.,2002);镜像法假设应力、速度分量在边界网格两侧以奇函数分布反应应力边界(Robertsson,1996);虚拟层方法在自由表面
引文
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